🚀 go-pugleaf

In article <BGLENDEN.90Nov21142152@mandrill.cv.nrao.edu> bglenden@mandrill.cv.nrao.edu (Brian Glendenning) writes:
>Do real compilers ever complain about [aliasing]? Or do FORTRAN compilers
>just assume that that users will never alias subroutine arguments?

  I haven't seen one which complained, but there may be some out
there.  Of course, detecting aliasing in general is a hard problem;
it's quite possible the compiler simply assumes the user knows what
he's doing, and doesn't try to detect the special cases.

  I'm also not sure if the FORTRAN standard allows parameters to be
aliased if they aren't changed in the called subroutine; I've seen a
lot of FORTRAN code which looks like CALL X(A,N,N) for instance.
Since the intent seems to be to allow either pass-by-reference or
pass-by-value-result, I have a hard time coming up with a scenario
where this *wouldn't* work (assuming, of course, that the two formal
parameters are used in a read-only way)...but it might not be legal.

	Anton
   
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| Anton Rang (grad student) | rang@cs.wisc.edu | UW--Madison |
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